When your code works then you have this inclination to add an extra feature and after adding it ,it works after catching a few bugs but then .... you feel so smug with yourself you add another feature and that stuff ups all YOUR CODE !!!and if you haven't saved a copy of the program before editing y0ur program so the eaaiset option you have I to use CTRL -Z and if you have been altering your code a lot the undo action only goes back a few alterations and hasn't undone your extra feature then you have to manually find the feature and clean it from your code taking longer then creating the program as a whole
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The undo action needs to save more alterations of the code 😑